All very true, but also just confirms how unacceptable this BA fiasco is.
The principles were the same in my thirty-odd years, but the discipline wrt software was that anybody/any team can write a system to do the required task and demonstrate it working with test data. Only the good snd well-trained treated that as 10% of the work needed before sending it live.
The other 90% was programming to cater for all possible forecastable errors or failures, and any unexpected events, were handled gracefully. That being written into the system and programming specs, and coded in as each routine was written.
Similarly at least two thirds of the testing was of these.
Senior company management were cutting out the budget for that vital 90% by the end of my first ten years. It has been one of the major cost savings that were so easily made.
The security aspects that you deal with of course didn't exist in the early days, so we didn't need to think about them. Those came later, first with mainframe dumb terminals and later PCs with floppy disk drives. They added an increasing complexity, as we all know now we have rampant hacking, phishing and the rest. Keeping you in employment

.
This BA failure though is, we are told, down to what is apparently the one and only central datacentre going down. Whether it was a power failure, a piece of kit causing it, or we are being lied to and it was a software bug or some other cause is not really the point. There had to be redundant mirror hardware or similar at at least one other site, and regular systematic testing of hardware systems, sub-systems or comms failure.
As per my link to distributed databases.
BA has, (or had until the LSE opens on Tuesday!), a market capitalisation of £12.9bn and �22.5bn revenues in 2016. (Sorry for mixing currencies, in bed holding an iPad up in one hand and typing with one finger).
It can fund resilient systems.
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